Balance arbor assembly for buffing and like machine

ABSTRACT

A work finishing wheel unit is clamped to a driving arbor by a pair of like holder collars between which conventional buff elements of the unit are held; and these collars each have an annular, dove-tail sectioned groove adjacent the outer periphery thereof. Mating balancing weights, also of dove-tail cross section, have slidable adjustment circumference-wise in the groove, being manually movable annularly to a desired balancing position, then fixedly clamped to the collar by a set screw to serve as a balancing counterpoise.

United States Patent Carlson [451 May 16, 1972 [54] BALANCE ARBORASSEMBLY FOR BUFFING AND LIKE MACHINE George R. Carlson, 830 CranbrookRoad, Birmingham, Mich. 48009 22 Filed: July 2,1970

21 Appl.No.: 51,985

[72] Inventor:

[52] US. Cl v ..74/573, 51/169 [51] Int. Cl ..Fl6f 15/32 [58] FieldofSearch ..74/573;5l/l69 56] References Cited UN lTED STATES PATENTS2,958,165 11/1960 Hofmann ..74/573X 430,270 6/1890 Cook ..74/573 PrimaryExaminer-Meyer Perlin Assistant Examiner-F. D. ShoemakerAttorney-Whittemore, l-lulbert & Belknap [5 7] ABSTRACT A work finishingwheel unit is clamped to a driving arbor by a pair of like holdercollars between which conventional buff elements of the unit are held;and these collars each have an annular, dove-tail sectioned grooveadjacent the outer periphery thereof. Mating balancing weights, also ofdove-tail cross section, have slidable adjustment circumference-wise inthe groove, being manually movable annularly to a desired balancingposition, then fixedly clamped to the collar by a set screw to serve asa balancing counterpoise.

5 Claims, 2 Drawing Figures PATENTEDMAY 16 m2 3.662.620

FIG.| /35 INVENTOR. GEORGE R. CARL N -'-l'- BY I A TQRNEYS BALANCE ARBORASSEMBLY FOR BUFFING AND LIKE MACHINE BACKGROUND OF THE INVENTION 1.Field of the Invention The invention finds application in a wide varietyof rotary buffing, polishing or like finishing wheel machines, as wellas abrasive wheel or belt installations, in which it is desired to truethe balance of a finishing wheel of one sort or another, or the rotativebalance of a contact wheel backing an abrasive or like belt, thus toinsure a most efficient and trouble-free operation thereof from theoutset of use. The improvement also finds corrective application in manycases in which a relatively soft structured working buff is subjected tosevere wear over a period of use resulting in a disturbance of thecentrifugal balance of the wheel. This occurs commonly when the normalfrictional wear on the wheel buffs (itself not necessarily distributeduniformly in even a purely rotative engagement) is compounded by ashifting of the work piece axially across the face of the wheel, or viceversa.

2. Description of the Prior Art I an unaware of any pertinent priorpatented art of the general nature of the balancing assembly hereindisclosed. However, makeshift attempts have been made in the past andcontinue to be made, to more or less crudely modify new and usedfinishing equipment to impart or restore rotative wheel balance. Thus ithas been the practice, for example, in attempting to true up buffing orlike wheels (often far from accurate as to balance as fabricated) toproceed, in the case of a unit comprised of an axial assembly of likebuff components, by shifting the latter angularly relative to oneanother in an effort to compensate a lack of balance of one component bythat of another, and so one. This hit or miss procedure usually leavesmuch to be desired in result; furthermore, even it is not available inthe case of a wheel comprising a single, axially elongated buffcomponent. This is also true in the case of an abrasive belt-backingroll or wheel, in which true balance is equally desirable. Abrasiveflap-type wheels are usually offbalance as produced.

The problem also arises in instances in which an improper or unevenspray application of a dressing composition to a wheel or wheelcomponent results in a loss of balance and resultant bounce in action. Acomplete new re-dressing of the wheel is normally in order.

Another corrective procedure has been to drill a hole or holes in awheel hub to reduce its weight locally and correct the wheels balance.But even if the procedure is temporarily successful, normal operationmay well again and soon render the wheel out of balance.

SUMMARY OF THE INVENTION As illustrated herein in a very simple version,the balanced wheel assembly comprises a pair of identical, hencereversely or interchangeably utilizable, holder annuli or collars ofcircular outline between which a series of buffing or polishing discs,for example, are clamped in the axial sense, one of the collars havingaxial engagement with an appropriate fixed shoulder or like stopformation on a rotary wheel drive shaft or arbor. The other collar isthen held in clamped engagement with the opposite side of the buff unit,as by nut means threadedly engaged on a reduced cross section part ofthe arbor.

Pursuant to the invention, the identical collars each have one or morecircumferentially adjustable balancing weights matingly received in acircumferential, axially outwardly facing groove of dovetail section onthe exposed side of the collar and each weight, when positioned asdesired, is clamped by a set screw to hold it in that position.

Thus, assuming that a finishing wheel unit, as typically constituted byan axial stack of relatively soft buffing discs, goes out of properbalance due to unequal or uneven wear, it requires only a brief stoppageof the equipment to enable an attendant to shift one or more of thebalancing collar weights, including weights at either axial side or bothsides of the wheel assembly, and set screw reclamp it in acircumferentially adjusted position. The same procedure applies to newwheels, of

course.

In such position, not only is the wheel imbalance compensated out interms of unbalanced radial throw; but the use of correspondingindependent weights on opposite sides of the buff unit enables the throwto be kept in perfect balance also in the axial sense, and withouttendency to cant the centrifugal effect out of a plane at a truetransverse angle to the axis of rotation.

While a wheel buff structure is herein shown and described, this type offinishing or polishing unit usage is simply illustrative; other more orless abrasive yet wearable wheel units may be balanced as desired by theprovisions of the invention; as indicated above, and whether as aninitial corrective treat mentor after the imbalance arises in use.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a sectional view, partiallybroken away, in a plane including the axis of rotation of the balancedarbor assembly ofthe invention, ie., in the plane ll ofFIG. 2; and

FIG. 2 is a fragmentary view in section along broken line 2 of FIG. 1.

DESCRIPTION OF A PREFERRED EMBODIMENT The wheel assembly of theinvention, generally designated 10, is shown as being mounted on adriver shaft or arbor 12, a main full diameter portion 13 of this shafthaving a somewhat reduced diameter, intermediate buff-mounting portionor section 14 which is threaded at 15 on its right hand end (FIG. 1).The arbor is further reduced suitably to a diameter at 16; and it is tobe understood that the arbor portions 13 and 16 will be appropriatelymounted in suitable bearing means, not shown.

A conventional stack unit or sub-assembly of fabric wheel buffs 18 isfixedly clamped between a pair of identical, but oppositely oriented,buffer holder collars 20 and 21, of which the left hand collar 20surrounds the reduced diameter intermediate shaft section 14 with areasonably close clearance, bottoming axially to its left (FIG. 1)against a stop shoulder 23 formed by the turning of the intermediateshaft section or portion 14. In this connection, it is to be understood,as indicated above, that the version 10 of the balanced wheel assemblyherein dealt with is of a highly simplified nature; and that variousstop or other provisions differing in nature from those herein shown maywell be resorted to if seen fit, or if other considerations of design soindicate.

The opposite or right hand collar 21 serves as a clamping collar for thestack of finishing discs 18. Its relation radiuswise to the intermediateshaft portion 14 is the same as that of the stop collar 20, thoughoriented oppositely in the axial sense, as indicated above. Each of thecollars 20 and 21 is provided with a pair of diametrically opposedkeyways 25; and the intermediate shaft portion 14 is provided withdiametrically opposed, axially elongated keyways 26; so that elongatedkeys 27 disposed in the radially facing keyways 25, 26 serve to lock thecollars 20, 21 and the bufiing elements 18 clamped by the collars forrotation as a unit as driven by shaft 12. Collar 21 is typically heldclamped in this driving relationship through the agency of a ring nut 28applied to and taken up tightly on threaded shaft portion 15, with anappropriate annular shim or washer 29 interposed between nut and collar.

In accordance with the invention, each of the collars 20, 21 is providedon its axially outwardly facing surface or side, and quite closelyadjacent the outer periphery thereof, with a dove-tail or truncatedV-shaped circular groove coaxial with the shaft 24, the grooves beinggenerally designated by the reference numeral 30 and affording anarcuate guide track for certain weights to be described. The grooves areof uniform cross section throughout almost a full 360 arcuate extent,opening outwardly between radially inner and outer angle edges 31, 32and being bottomed by a 360 extending base surface 33. However, as bestshown in FIG. 2, each groove 30 has its said edges 31, 32 interrupted atone small circumferential area or zone by radially opposed notches 34,35, respectively. These may be considered to define, in effect, parts ofa generally keystone-shaped access opening to the groove 30, suchopening being indicated in dot-dash line in FIG. 2 and designated 36;its purpose is to be described.

Groove 30 is adapted to slidably receive one or more adjustablebalancing weights 38, actually shown as three in number, which, in aperfectly balanced condition of the wheel structure 10, will naturallybe disposed in 120 annular spacing from one another, or nearly soconsidering the weight factor introduced by opening 36. Each of theweights is of a generally keystone or truncated triangular outline at anouter, relatively massive body portion 39 thereof, at which its mass isin the main concentrated; and each weight 38 has an integral guideportion 40 of similar shape whose cross section is dovetailed to mateslidably at its angled radial edges within the correspondinglydove-tailed groove 30. The circumferential width of the portion 41 isslightly less than that of the access opening 36 to enable the weightsto be easily introduced into and removed from the groove 30 as desired.

Each weight 38 is drilled and tapped through its radial midpoint toreceive a small Allen or socket-head set screw 42 which, when tightlytaken up in engagement against the base 33 of groove 30, will hold theassociated weight tightly in an adjusted position. In the unlikely eventof any of these set screws becoming loose, a further knurled head setscrew 43 is tightly threaded into a tapped opening 44 in the basesurface 33, centrally of the area of the latter projected by the accessopening 36. Should a weight holding screw become loose, the screw 43will prevent its dropping out of the groove 30 until the wheel unit isstopped and the weight is properly adjusted and secured.

FIG. 2 shows the balanced assembly with its three weights 38 positionedas depicted in solid line; while the weights are otherwise shown indotted line in a typical position to which they may have been adjustedand reclamped to correct an unbalanced wheel condition arising from wearor the like. Naturally the spacing of any or all of the weights 38 maybe altered as desired or found necessary, ie., they need not necessarilyhave approximately equal 120 spacing from one another.

The simple provisions described here render it unnecessary as in thepast for an operator to correct a loss of proper wheel balance byresorting to some sort of crude procedure such as has heretofore beenutilized, as briefly mentioned above. A loss of balance, particularly inthe case of solid abrasive disk of a harder sort, may well result in atotal destruction of an entire head structure. However, with the use ofbalancing means according to the invention it is only necessary for anattendant, with but a brief stoppage of wheel operation and at mostemploying a simple hand tool, to make a necessary balancerestoringadjustment.

What is claimed is:

l. A balanced rotative wheel structure, comprising a rotative driver orlike operator member, a finishing or related wheel unit drivinglyconnected to said member and presenting an axially facing radial sidesurface, and means effecting the driving connection between saidoperator member and unit and enabling an adjustment of the rotativebalance of said unit, comprising an annular member rotatable with saidunit and provided with axially extending key means at least in partdrivingly connecting the same with said operator member, said annularmember affording a guide track in an outer axially facing side thereofconcentric with the rotative axis of said structure, and an inneroppositely facing side for flush abutting engagement with said sidesurface of the wheel unit, at least one balance weight having a portionreceived by said track for arcuate adjustment relative to the latter andanother portion projecting axially outwardly of said axial side of theannular member, and means to hold said weight in an annularly adjustedposition in said track.

2. The structure of claim 1, in which there are two of said annularmembers, bein similar to one another and resentin the respective trackst ereof on opposite axial sr es of sar wheel unit, and annular membersclamping said unit therebetween to drivingly connect the latter withsaid operator member.

3. The structure of claim 2, in which said tracks are dovetail shapedgrooves formed in axially outwardly facing surfaces of the respectivepart members, the portions of the I weights received therein being alsoof dove-tail shape to mate slidingly in the groove.

4. The structure of claim 3, in which the weights have set screw typemeans engageable with the respective annular members to hold the weightsin adjusted positions.

5. The structure of claim 4, in which each of said grooves has at leastone enlarged, outwardly facing access opening for the placement orremoval of weights.

UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No.3,662,620 Dated May 16, 1972 Inventor George R. Carlson It is certifiedthat error appears in the above-identified patent and that said LettersPatent are hereby corrected as shown below:

In Claim 2, column 4, line 31, change "and" to -said-.

In the title, change "Balance to -Balanced-.

Signed and sealed this 25th day of July 1972.

(SEAL) Attest:

EDWARD M.FLETCHER,JR. ROBERT GOTTSCHALK Attesting Officer Commissionerof Patents FORM PC4050 (10459) I uscoMM-Dc 60376-P69 w US, GOVERNMENTPRINTING OFFICE C 959 0366-33

1. A balanced rotative wheel structure, comprising a rotative driver orlike operator member, a finishing or related wheel unit drivinglyconnected to said member and presenting an axially facing radial sidesurface, and means effecting the driving connection between saidoperator member and unit and enabling an adjustment of the rotativebalance of said unit, comprising an annular member rotatable with saidunit and provided with axially extending key means at least in partdrivingly connecting the same with said operator member, said annularmember affording a guide track in an outer axially facing side thereofconcentric with the rotative axis of said structure, and an inneroppositely facing side for flush abutting engagement with said sidesurface of the wheel unit, at least one balance weight having a portionreceived by said track for arcuate adjustment relative to the latter andanother portion projecting axially outwardly of said axial side of theannular member, and means to hold said weight in an annularly adjustedposition in said track.
 2. The structure of claim 1, in which there aretwo of said annular members, being similar to one another and presentingthe respective tracks thereof on opposite axial sides of said wheelunit, and annular members clamping said unit therebetween to drivinglyconnect the latter with said operator member.
 3. The structure of claim2, in which said tracks are dove-tail shaped grooves formed in axiallyoutwardly facing surfaces of the respective part members, the portionsof the weights received therein being also of dove-tail shape to mateslidingly in the groove.
 4. The structure of claim 3, in which theweights have set screw type means engageable with the respective annularmembers to hold the weights in adjusted positions.
 5. The structure ofclaim 4, in which each of said grooves has at least one enlarged,outwardly facing access opening for the placement or removal of weights.